The Economist Intelligence Unit — which rates 133 global cities, and compares the price of a basket of 138 everyday items in each — has ranked them as joint top of the table.
The European cities have leapfrogged over Singapore and Osaka, which tied with Hong Kong in the previous Worldwide Cost of Living Survey, carried out in March.
The changes are especially marked this time around, with the report doubling as an assessment of the impact of the Covid-19 pandemic on prices around the world.
Currency fluctuations due to the pandemic mean that destinations in Africa, the Americas and Eastern Europe have got less expensive since March.